Dirac’s and Born’s Contributions

In parallel with W. Heisenberg[aut]Heisenberg, Werner Karl and E. Schrödinger[aut]Schrödinger, Erwin, but independently from them, also P.A.M. Dirac[aut]Dirac, Paul Adrien Maurice developed a formalization of quantum mechanics. In this chapter, we will present Dirac’s general and abstract version of quantum mechanics together with his new—and now universally adopted—formalism. We will proceed by making a discussion on the equivalence of the two theories of quantum mechanics—the one proposed by M. Born[aut]Born, Max, Heisenberg[aut]Heisenberg, Werner Karl and P. Jordan[aut]Jordan, Pascual, which exploited a matrix approach, and the one developed by Schrödinger[aut]Schrödinger, Erwin, with his wave interpretation. Finally, we will discuss in some detail the probabilistic interpretation of the wavefunction provided by M. Born[aut]Born, Max with some observations on its physical implications.